The present invention relates to a tampon insertion device and, more particularly, to a preferably short and compact type.
The tampon applicator assembly consists of an outer tube (the insertion tube or barrel)having a forward end (leading end or insertion end, or distal discharge end), a tampon positionable within the outer tube immediately inward of its leading end, and an inner tube (ejection tube or plunger, or pusher, or ejector) telescopically receivable within the outer tube rearwardly of the tampon and functioning as the pusher for effecting the forward delivery of the tampon through the leading end of the outer tube.
As known, the tampon applicator is introduce vaginally and, subsequent to the forward delivery of the tampon, is withdrawable.
Tampon applicators are commonly of two types, distinguished from each other by their length.
Conventional type applicators are usually of the ready-for-use type whereas compact type applicators have to be prepared for use by the user.
In the conventional type applicator, the tampon is located inside the leading potion of the outer rube, and the inner tube or the pusher is located within the outer tube rearwardly of the tampon.
In the compact type applicator, the tampon (or at least the greater portion thereof) is located within the inner tube. In operational use, the user has to hold the rear end of the outer tube by the fingers of one hand and grip the rear end of the inner tube to retract it by the fingers of the other hand so that front end of the inner tube will be behind rear end of the tampon.
The length of the outer tube of all types of applicators desirably should be approximately 23/4" in order to satisfy the necessity of placing the tampon to depth approximately 2" to rear end of the tampon and to have a gripping area approximately 3/4" in length.
The rear part of the inner tube will extend from the rear open end of the outer tube approximately 2" so as to give possibility for a full expulsion of the tampon through leading end of the outer tube. For this reason, the conventional type applicator has a full length of approximately 43/4.
Contrariwise, in the compact type applicator, the rear part of the inner tube extends from the rear open end of the outer tube between 3/8" to 5/8". The overall length of the assembled applicator is approximately 31/4".
Any attempt to fabricate an applicator significantly shorter will lead to at least one salient disadvantage: a wrong location of the tampon in the catamenial canal, or a minimized convinience of the gripping of the rearward end of the inner tube for its retraction or an increased overall diameter of the applicator.
To facilitate inner tube retraction, any compact applicator has to comprise a tampon holding means associated with the outer tube for engaging a tampon carried in the inner tube so as to resist rearward movement of the tampon, while permit its forward movement through the discharge end of the outer tube during expelling of the tampon into the body cavity.
Lately it has been introduced a lot of structural solution of the tampon holding means, which can be divided into three major groups.
First group includes the applicators which comprise an additional part, such as the inner sleeve located between inner and outer tubes shown in U.S. Pat. No 4,676,773. The necessity to fabricate an additional part and the using of more complicated assembling machinery disadvantageously increase the cost of production of such tampon applicators. Besides, the tampon applicator according to U.S. Pat. No 4,676,773 suffers disadvantage from the user's safety standpoint. Very often the rear end of a tampon has an unbound particle, which, in this particular applicator structure, can be tangled between ring 12 and folded flange 11(see FIG. 11 of U.S. Pat. No 4,676,773). If this happened, the outer tube will be withdrawn alone. The withdrawal of the remaining parts of the applicator can necessitate emergency medical assistance.
Second group includes the applicators, in which tampon holding means comprises at least one projection, fixed to inner surface of outer tube, extending inwardly through a longitudinal window in the inner tube and located rearwardly of rear end of the tampon. Such applicators are described in U.S. Pat. Nos 4,276,881; 4,286,595; 4,291,596; 4,891,042. All applicators of this group suffer from the same disadvantage following from necessity of additional rotational orientation of the tubes prior to the assemblage of the applicator.
Third group includes the applicators in which tampon holding means located adjacent of the discharge end of the outer tube and coacts with the front end of the tampon. The applicator described in U.S. Pat. No 4,479,791 has a tampon completely stored in the inner space of the inner tube and tampon holding means in the form of thin elongated projections extending from inner surface of the outer tube inwardly through the openings between long fingers of the inner tube. Because of such structure, this applicator suffers the same disadvantage as the second group of applicators. Another disadvantage follows from a weakness of narrow long fingers of the inner tube. Sometimes they are not able to transfer to the tampon a longitudinal force applied to the rear end of the inner tube during expelling of the tampon. If they are bent and smashed, the tampon will be positioned improperly. Besides, if the tampon is highly compressed, those projections can be bent in the circumferential direction during the assembly of the applicator. In this case, the projections loose ability to hold tampon during partial withdrawal of the inner tube and such applicator cannot be used.
Each of the above listed patents is assigned to one of the major tampon manufacturers, but none of those tampon applicators had been commercially successful so far.
At the present time only one compact tampon applicator is commercially available, and it is fabricated in accordance with U.S. Pat. No 4,726,805 (used hereby as a reference). This patent describes an applicator with a tampon holding means comprising a set of flaps located circumferentially closely adjacent to the bases of the petals defining the leading end of the outer tube. Each flap is a thin circumferentially extended projection flexible in axial direction.
The flaps cannot sufficiently hold the portion of the tampon extending from the inner tube, if the tampon fabricated of straight cylindrical configuration. To increase tampon holding effect the extended portion made in form of a head, enlarged in diameter and positioned in front of the flaps.
Actually, many of these tampons have misalignment of the head and the remaining portion. Such tampons have the shoulder behind the head on one side and do not have it on the diametrally opposed side. Functional reliability of the applicator assembled with such tampon decreases, especially if a user uses applicator in environment existing in a public toilet.
So, this applicator necessitates the use of more complicated tampon making machinery, but does not provide reliable enough tampon applicator assembly.